Batch procedure for the regeneration of predominantly clay bound foundry-old sand

摘要

The clay-bonded used casting sand is treated in a drum rotated about a horizontal axis by continuously feeding a sand additive to the drum in an amount sufficient to maintain the quantity of sand in the drum at about 26-40 percent by volume of the drum to compensate for the amount of shell material drawn off by pneumatic dust removal devices so as to maintain an optimal relationship between the volume of the drum in the quantity of sand in the drum over the entire period of treatment. The amount of sand fed to the drum may be controlled by the amount of current consumed by a motor used for rotating the drum.